1. Impact of EBUS-TBNA in addition to [18F]FDG-PET/CT imaging on target volume definition for radiochemotherapy in stage III NSCLC
- Author
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Hubertus Hautzel, Lale Umutlu, Rüdiger Karpf-Wissel, Axel Wetter, Nika Guberina, Dirk Theegarten, Martin Stuschke, Maja Guberina, Wilfried Eberhardt, Martin Schuler, Clemens Aigner, Ken Herrmann, Till Ploenes, Kaid Darwiche, and Christoph Pöttgen
- Subjects
Lung Neoplasms ,medicine.medical_treatment ,Planning target volume ,Hilum (biology) ,non-small cell lung cancer (NSCLC) ,Non-small cell lung cancer (NSCLC) ,03 medical and health sciences ,0302 clinical medicine ,Fluorodeoxyglucose F18 ,Carcinoma, Non-Small-Cell Lung ,Positron Emission Tomography Computed Tomography ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Target volume definition ,Neoplasm Staging ,Retrospective Studies ,EBUS-TBNA ,Radiation ,Radiotherapy ,business.industry ,Mediastinum ,General Medicine ,Chemoradiotherapy ,medicine.disease ,[18F]FDG-PET/CT ,Primary tumor ,Radiation therapy ,Exact test ,Lymphatic system ,medicine.anatomical_structure ,030228 respiratory system ,Stage III ,030220 oncology & carcinogenesis ,Original Article ,Lymph Nodes ,Nuclear medicine ,business - Abstract
Purpose/introduction [18F]FDG-PET/CT is the standard imaging-technique for radiation treatment (RT) planning in locally advanced non-small cell lung cancer (NSCLC). The purpose of this study was to examine the additional value of endobronchial-ultrasound transbronchial needle aspiration (EBUS-TBNA) to standard PET/CT for mediastinal lymph-node (LN) staging and its impact on clinical target volume (CTV). Materials and methods All consecutive patients with primary stage III NSCLC who underwent [18F]FDG-PET/CT and EBUS-TBNA prior to RT were analyzed from 12/2011 to 06/2018. LN-stations were assessed by an expert-radiologist and a nuclear medicine-physician. CTV was evaluated by two independent radiation oncologists. LNs were grouped with increasing distance along the lymphatic chains from primary tumor into echelon-1 (ipsilateral hilum), echelon-2 (LN-station 7 and ipsilateral 4), and echelon-3 (remaining mediastinum and contralateral hilum). Results A total of 675 LN-stations of which 291 were positive for tumor-cells, were sampled by EBUS-TBNA in 180 patients. The rate of EBUS-positive LNs was 43% among all sampled LNs. EBUS-positivity in EBUS-probed LNs decreased from 85.8% in echelon-1 LNs to 42.4%/ 9.6% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). The false discovery rate of PET in comparison with EBUS results rose from 5.3% in echelon-1 to 32.9%/ 69.1% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). Sensitivity and specificity of FDG-PET/CT ranged from 85 to 99% and 67 to 80% for the different echelons. In 22.2% patients, EBUS-TBNA finding triggered changes of the treated CTV, compared with contouring algorithms based on FDG-avidity as the sole criterion for inclusion. CTV was enlarged in 6.7% patients due to EBUS-positivity in PET-negative LN-station and reduced in 15.5% by exclusion of an EBUS-negative but PET-positive LN-station. Conclusion The false discovery rate of [18F]FDG-PET/CT increased markedly with distance from the primary tumor. Inclusion of systematic mediastinal LN mapping by EBUS-TBNA in addition to PET/CT has the potential to increase accuracy of target volume definition, particularly in echelon-3 LNs. EBUS-TBNA is recommended as integral part of staging for radiochemotherapy in stage III NSCLC.
- Published
- 2021